1. Technical Field
The present invention relates to a cleaning device used in an image forming apparatus which uses a liquid developer including toner particles and carrier liquid, and an image forming apparatus provided with such a cleaning device.
2. Related Art
As an image forming apparatus which uses a liquid developer, for example, an apparatus is disclosed which has a photo conductor drum on which a latent image is formed, a developing device (developing section) which forms an image on the photo conductor drum by developing the latent image by the liquid developer, a primary transferring member which primarily transfers the image on the photo conductor drum to the image supporting surface of a circulating intermediate transferring belt (image supporting body), and a secondary transferring roller which comes into contact with the image supporting surface with a recording material (recording medium) interposed therebetween, thereby transferring the image transferred to the image supporting surface to the recording material (referring to FIG. 1, etc. of JP-A-2001-166611).This type of image forming apparatus has a number of rotating or circulating members (a latent image supporting body, a primary transferring roller, a secondary transferring roller, and the like; hereinafter referred to as holding members) which have holding surfaces that hold the liquid developer. Then, the liquid developer is removed from the holding surface by bringing a contact corner portion (edge portion) of a cleaning blade into contact with the holding surface of the holding member.
Here, the cleaning blade applied to the holding member (for example, the secondary transferring roller) has the contact corner portion constituted at the joining portion (ridge line) of one end surface (hereinafter referred to as a “contact side end surface”) and a surface facing the outer circumferential surface of the holding member. Further, the cleaning blade is supported on a blade supporting body which is disposed so as to be able to be rocked with a given rocking shaft as a base, and the contact corner portion is brought into contact with the holding surface of the holding member in a pressed state by pressing the blade supporting body by a spring (pressing member). Then, the contact corner portion which is in a pressed state scrapes off unnecessary liquid developer and the like from the holding surface.
However, in this type of cleaning device, unbalance may occur in the contact pressure of the cleaning blade with a cleaned body (namely, the holding member). For example, in a case where the spring for applying a pressing force (biasing force) to the above-mentioned blade supporting body is mounted on the central portion along the shaft center of the blade supporting body, if deviation (for example, deviation within a manufacturing tolerance) occurs in the attaching position of the spring or in the shaft center of the blade supporting body, when the cleaning blade has been brought into contact with the cleaned body, unbalance may occur between the contact pressure of one end portion side of the cleaning blade with the cleaned body and the contact pressure of the other end portion side of the cleaning blade with the cleaned body.
In such a case, unforeseen inclination from one end portion side of the contact corner portion toward the other end portion side is generated, so that liquid developer collected in a region (hereinafter referred to as a “retention portion”) surrounded by the outer circumferential surface and the contact side end surfaces of the cleaned body may be possibly biased to and distributed at a region located on one end portion side or the other end portion side of the contact corner portion in the retention portion. In this case, the liquid developer in the retention portion may drop across one end portion side or the other end portion side of the contact corner portion, thereby contaminating the inside of the image forming apparatus.